Cure promoter compositions and methods for the same

ABSTRACT

A cure promoter composition is disclosed, including an accelerator which may include a thiocarbamate, a hydrated thiocarbamate, a dithiocarbamate, a thiazole, a mercaptothiazole, a sulfenamide, a thiazolesulfenamide, a metal salt of thiocarbamate, sulfur chloride, or combinations thereof. The cure promoter composition also includes a compatibilizing carrier, one or more organic solvents, a catalyst, an optional reducing agent, an optional reactive silane, an optional reactive organometallic, an optional gelling agent, and an optional aqueous component. A method for applying the cure promoter composition is disclosed, including contacting the organic solvents, the accelerator, the carrier, the reactive silanes, the reactive organometallics, the reducing agents, and the catalyst with one another to prepare the cure promoter composition, homogenizing the cure promoter composition, pausing after homogenizing to allow the cure promoter time to react, applying a sealant onto a substrate, and applying the cure promoter composition to a surface of the sealant.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 17/654,248 filed Mar. 10, 2022 and claims priority to U.S.Provisional Patent Application No. 63/180,732, filed on Apr. 28, 2021,the entireties of which are incorporated by reference herein.

TECHNICAL FIELD

The present disclosure generally relates to the field of sealants. Moreparticularly, the present disclosure relates to compositions forimproving the process efficiency of the application of polymericmaterials, such as polysulfide sealants with the use of a cure promoter.

BACKGROUND

Sealants play a vital role in the successful assembly of variousaircraft components and see widespread use in both manufacturing andmaintenance. In particular, sealants are used extensively in fuel tankapplications within the aircraft structure as fastener fillets or as gapfillers. For example, commercial aircrafts that store fuel in wingsand/or tanks located between the wings do not rely on bladders or linersto contain the fuel. Instead, commercial aircrafts may have metallic orcomposite fuel tanks as a primary structure to contain the fuel. As aresult, joints and bolts must be properly sealed to eliminate fuelleakage, mitigate corrosion potential, and protect against arcingelectrical discharge in the fuel storage in the event of a lightningstrike.

Conventional application of the sealant at or around the area of thejoints and bolts includes cleaning the area with a solvent andsubsequent application of an adhesion promoter, or a Class A material(e.g., Class A polysulfide sealant, brushable sealant, etc.). Afterapplication of the adhesion promoter, a thioxotropic sealant (e.g., aClass B polysulfide sealant) can be applied and allowed to cure tocomplete the sealing system. The curing of the sealing system is often alengthy process (e.g., up to 24 hours or more) that slows aircraftproduction and maintenance efficiencies.

What is needed, then, are improved compositions for improving processefficiency for sealant application and more efficient methods forpreparing and utilizing the improved compositions and processes.

SUMMARY

The following presents a simplified summary in order to provide a basicunderstanding of some aspects of the present teachings. This summary isnot an extensive overview, nor is it intended to identify key orcritical elements of the present teachings, nor to delineate the scopeof the disclosure. Rather, its primary purpose is merely to present oneor more concepts in simplified form as a prelude to the detaileddescription presented later.

A cure promoter composition is disclosed. The cure promoter compositionincludes an accelerator which may include a thiocarbamate, a hydratedthiocarbamate, a dithiocarbamate, a thiazole, a mercaptothiazole, asulfenamide, a thiazolesulfenamide, a metal salt of thiocarbamate,sulfur chloride, or combinations thereof. The cure promoter compositionalso includes a compatibilizing carrier. The cure promoter compositionalso includes one or more organic solvents. The composition alsoincludes a catalyst. The cure promoter composition also includes anoptional reducing agent. The cure promoter composition also includesoptionally, one or more reactive silanes. The composition also includesone or more optional reactive organometallics, one or more optionalgelling agents, and an optional aqueous component.

Embodiments of a cure promoter composition are disclosed where theaccelerator is disulfiram. In certain embodiments, the compatibilizingcarrier may include a monomer, an oligomer, a low molecular weightpolysulfides, a low molecular weight polythiol, a low molecular weightvinyl functional compound, an organic solvent, or combinations thereof.The cure promoter composition may include pentaerythritoltetrakis(3-mercaptopropionate), trimethylolpropanetris(3-mercaptopropionate), 2,2′-thiodiethanethiol,2,2′-(ethylenedioxy)diethanethiol, tris(mercaptoalkyl) cyclohexanes, orcombinations thereof. The compatibilizing carrier may include allylmonosulfide, allyl disulfide, ethyl vinyl sulfide, phenyl vinyl sulfide,styrene, or combinations thereof. The one or more organic solvents inthe cure promoter composition may include an aliphatic hydrocarbon, anaromatic compound, a ketone, an amine, an ester, an alcohol, analdehyde, an ether, or combinations thereof. The catalyst of the curepromoter composition may include an amidine, a diazole, an amine, apyridine, or combinations thereof. The cure promoter composition mayinclude one or more reducing agents, the reducing agent may includecysteamine, betamercaptoethanol, dithiothreitol, tris(2-carboxyethyl)phosphine hydrochloride, dithiobutylamine, glutathione, or combinationsthereof. The cure promoter composition may include one or more reactivesilanes, the one or more reactive silanes may include aglycidoxypropyltrimethoxysilane, a mercaptopropyltrimethoxysilane, orcombinations thereof. The cure promoter composition may include one ormore reactive organometallics, the one or more reactive organometallicsmay include a reactive titanate, a reactive zirconate, a reactivealuminate, or combinations thereof. The cure promoter may include one ormore gelling agents, and where the cure promoter composition having oneor more gelling agents may have a viscosity of about 0.001 to about 2000pas at a shear rate of about 0.1 to about 100 sec-1. The cure promotercomposition may include no gelling agent wherein the cure promotercomposition has a viscosity of about 0.001 to about 50 pas at a shearrate of about 0.1 to about 100 sec-1.

A method for applying the cure promoter composition is disclosed. Themethod for applying the cure promoter composition may include contactingthe one or more organic solvents, the accelerator, the compatibilizingcarrier, the one or more optional reactive silanes, the one or moreoptional reactive organometallics, the optional one or more reducingagents, and the catalyst with one another to prepare the cure promotercomposition, homogenizing the cure promoter composition, pausing afterhomogenizing to allow the cure promoter time to react, applying asealant, resin, paint layer, or combinations thereof onto a substrate,and applying the cure promoter composition to a surface of the sealant,resin, paint layer, or substrate. The method for applying the curepromoter composition may include pausing to allow the sealant, resin,paint layer, or combinations thereof to cure completely. The method forapplying the cure promoter composition may include abrading the surfaceof the sealant, resin, paint layer, or combinations thereof. The methodfor applying the cure promoter composition may include contacting afirst portion may include the one or more organic solvents, theaccelerator, and the catalyst in a first container, contacting a secondportion may include the one or more organic solvents the compatibilizingcarrier, the one or more optional reactive silanes, the one or moreoptional organometallics, and the optional one or more reducing agentsin a second container, and contacting contents of the first containerwith contents of the second container prior to applying the curepromoter composition to the substrate. The substrate may include analuminum surface, a carbon fiber composite surface, or combinationsthereof.

Another method for applying a cure promoter composition is disclosed.The method for applying a cure promoter composition also includescontacting one or more organic solvents, an accelerator which includes athiocarbamate, a hydrated thiocarbamate, a dithiocarbamate, a thiazole,a mercaptothiazole, a sulfenamide, a thiazolesulfenamide, a metal saltof thiocarbamate, sulfur chloride, or combinations thereof, acompatibilizing carrier, one or more optional reactive silanes, one ormore optional organometallics, and a catalyst with one another toprepare a cure promoter composition, and homogenizing the cure promotercomposition. The method for applying a cure promoter composition alsoincludes applying a sealant, resin, paint layer, or combinations thereofonto a substrate. The method for applying a cure promoter compositionalso includes applying the cure promoter composition to a surface of thesealant, resin, paint layer, or combinations thereof, evaporating theone or more organic solvents from the cure promoter composition, andpausing to allow the cure promoter time to react.

The features, functions, and advantages that have been discussed can beachieved independently in various implementations or can be combined inyet other implementations further details of which can be seen withreference to the following description.

DETAILED DESCRIPTION

During the assembly of various aircraft components, sealants andfinishes play an integral role in terms of component manufacturing andmaintenance. Sealants in particular are extensively used in fuel tankand other critical components to prevent leaks, corrosion, andelectromagnetic effects, such as lightning strikes. Current processesfor applying polysulfide and other sealants to aircraft components istime consuming and slows down efficient aircraft production andmaintenance. An exemplary process involving a fastener fillet sealingincludes, abrasion of a substrate panel, brush application of a lowviscosity Class A polysulfide sealant onto a surface or substrate. Afterthis first Class A sealant is applied, a thixotropic Class B polysulfidesealant is applied over the top of the Class A polysulfide sealant andallowed to cure.

Cure promoter compositions as described herein can improve theprocessibility and application efficiency of such sealants, inparticular providing enhanced bonding and curing efficiency within andbetween polymeric materials such as paints and sealants applied ontoaircraft or aerospace substrates such as aluminum and/or carbon fiberreinforced composites without additional preparation or process steps.These cure promoter compositions can be compositions of accelerators,compatibilizing carriers, catalysts, reducing agents, an aqueouscomponent, reactive organometallic species based on aluminum, titanium,zirconium or combinations thereof and combined with reactive silanecoupling agents dispersed in organic solvents (MEK, MIBK, etc). The curepromoter composition can be applied as a low viscosity solution orincorporated into a gelled solvent for enhanced application convenience.The use of a cure promoter along with a Class B sealant may eliminatethe need for additional materials and curing time for multiple layers ofsealant composition. Furthermore, surface tack-free time reduction andthrough cure via topical application can be improved, and the materialis effective on a variety of sealants. Additional benefits with the useof an optional gelling agent may facilitate the use of cure promoters ina higher viscosity or gel form, thus enabling their use in localizedapplication in a specific target area where the adhesion promoter mayremain where applied for an extended period if the surface ishorizontal, vertical, or inverted in an overhead location.

As used herein, “free” or “substantially free” of a material can referto a composition, component, or phase where the material is present inan amount of less than 10.0 weight %, less than 5.0 weight %, less than3.0 weight %, less than 1.0 weight %, less than 0.1 weight %, less than0.05 weight %, less than 0.01 weight %, less than 0.005 weight %, orless than 0.0001 weight % based on a total weight of the composition,component, or phase.

Additionally, all numerical values are “about” or “approximately” theindicated value, and take into account experimental error and variationsthat would be expected by a person having ordinary skill in the art. Itshould be appreciated that all numerical values and ranges disclosedherein are approximate values and ranges. The terms “about” or“substantial” and “substantially” or “approximately,” with reference toamounts or measurement values, are meant that the recitedcharacteristic, parameter, or values need not be achieved exactly.Rather, deviations or variations, including, for example, tolerances,measurement error, measurement accuracy limitations, and other factorsknown to those skilled in the art, may occur in amounts that do notpreclude the effect that the characteristic was intended to provide. Asused herein, “about” is to mean within +/−5% of a stated target value,maximum, or minimum value.

All references cited herein are hereby incorporated by reference intheir entireties. In the event of a conflict in a definition in thepresent disclosure and that of a cited reference, the present disclosurecontrols.

The present disclosure provides one or more cure promoter compositions.As used herein, the term “cure promoter” refers to a class of materialscomposed of an accelerator, a compatibilizing carrier, a catalyst, anoptional reducing agent, an optional gelling agent, an optional liquidreactive silane or reactive organometallic composition, and an optionalaqueous component within an organic solvent. The cure promotercompositions disclosed herein may include one or more optionalfunctional additives or agents capable of or configured to improve uponconventional methods of preparing a surface for treatment or applicationof a sealant. For example, as further described herein, the curepromoter compositions disclosed herein can be capable of or migrating ordiffusing within the bulk of an applied sealant or surface coatingmaterial, thereby effectively reducing processing or curing time of asealant or surface coating application, as well as any other preparationsteps such as sanding or surface abrasion. As the cure promoter migratesor diffuses into the bulk of a sealant material, it carries in anddisperses within a sealant material, ingredients that may participate inand/or enhance the crosslinking or curing properties of the sealantmaterial. Further, a “compatibilizing carrier,” as used herein, is aterm referring to a class of material that via its inherent lowviscosity, surface tension, or other properties, provides a means tohelp diffuse or migrate an accelerator, a catalyst, reactive silane,reactive titanate, or other functional material to disperse within thebulk of a sealant layer without any required mixing or agitation.Accordingly, the cure promoter composition disclosed herein providesmethods for reducing the amount of time necessary to seal a surface witha sealant, as compared to conventional methods, thereby reducingmanufacturing cycle times for the product being manufactured (e.g.,aircrafts), which leads to a significant cost savings. The cure promotercompositions disclosed herein are also capable of or configured toprovide or facilitate the identification of an area or surface treatedwith the cure promoter composition (e.g., via an indicator).

Compositions disclosed herein can be or include a cure promotercomposition including one or more accelerators, one or morecompatibilizing carriers, one or more catalysts, one or more organicsolvents, one or more reactive silanes, one or more reactiveorganometallics, one or more optional gelling agents, one or moreoptional functional additives, an aqueous component, or combinationsthereof. The cure promoter composition can be capable of or configuredto prepare a surface for subsequent treatment or application of asealant (e.g., polysulfide sealant) or be applied to the surface of asealant after application. For example, the cure promoter compositioncan be capable of or configured to clean the surface and/or prime asurface for subsequent treatment or application of a sealant. Forexample, the cure promoter composition can be capable of or configuredto clean the surface and/or prime a surface for subsequent treatment orapplication of polymeric materials, such as a polysulfide sealant. Thecure promoter composition can be capable of or configured to clean oneor more of lubricants, such as drilling lubricants, coolants, greases,waxes, or the like, or any combination thereof, from surfaces to betreated. For example, the cure promoter composition can be capable orconfigured to be applied to a sealant, polymer, or resin layer to causeor influence a crosslinking or curing reaction in the sealant, polymer,or resin layer by nature of its chemical composition and/or physicalproperties. Accordingly, the cure promoter compositions disclosed hereincan be referred to as multifunctional cure promoter compositions. Thecure promoter compositions for sealants and finishes as described hereinmay exhibit reaction with various substrates and sealants via multiplemechanisms. For example, some reactive organometallic preparations mayreact more rapidly than reactive silanes under various conditions and/orenvironments which may eliminate the necessity for lengthy processingsteps related to the application of finishes or sealants, including butnot limited to surface preparation steps such as sanding, abrading, andthe like. In some multifunctional cure promoters according toembodiments herein, the multifunctional cure promoter may also act as anadhesion promoter when applied between a substrate and a sealant. When amultifunctional cure promoter is applied in between substrate andsealant as an adhesion promoter, the substrate needs not to be sanded.When a multifunctional cure promoter is applied as a cure promoter ontop of the sealant, the sealant surface can be sanded after the reactiontime has elapsed.

The cure promoter composition may be applied to a substrate or a sealantsurface and provided reaction time to react either with atmosphericmoisture during application, resident functional group chemistry of thesubstrate or within the bulk of the sealant layer to improvecrosslinking or cure efficiency during a sealant application process.The cure promoter composition can have a reaction time in which thesurface becomes tack-free of from about 10 seconds (sec) to about 2hours (hrs), at a temperature of about 25° C. For example, the curepromoter composition can have a reaction time of from about 10 sec,about 60 sec, about 5 min, about 10 min, about 30 min, about 45 min, orabout 60 min to about 65 min, about 70 min, about 90 min, about 100 min,or about 120 min, at a temperature of about 25° C. An intermediate cureof the sealant may take place after exposure to the cure promoter for aperiod of from about 1 hour to about 6 hours at 25° C. A full cure ofthe sealant may take place after exposure to the cure promoter for aperiod of from about 6 hours to about 8 hours at 25° C. This can becontrasted with commercial sealants without cure promoters whichtypically take approximately 5 hours to about 6 hours to have atack-free surface and from about 6 hours to about 12 hours to completelyfully cure. It should be appreciated that the reaction time may bepresent during fabrication or preparation of the cure promotercomposition.

The cure promoter composition can exclude, be free, or substantiallyfree of agar and/or agar gels. For example, the cure promotercomposition can exclude, be free, or substantially free of agar as asolvent gel, such as in agar-based gels. The cure promoter compositioncan exclude, be free, or substantially free of organic or polymericgelling agents in certain embodiments.

The one or more reactive silanes, also referred to as silane adhesionpromoters or silane coupling agents, of the cure promoter compositioncan be capable of or configured to facilitate adhesion of a sealantapplied to a surface after treatment with the cure promoter composition.For example, the adhesion promoter can be capable of or configured topromote compatibility and/or adhesion between two different sealantlayers or between a sealant layer and a substrate, or combinationsthereof.

The cure promoter composition can include one or more accelerators. Asused herein, the term “accelerator” can refer to any component,compound, or substance that facilitates or promotes the curing of thepolymeric material, such as polysulfide sealants. Accelerants may beconsumed in the process of their reaction. Illustrative accelerators ofthe cure promoter composition can be or include, but are not limited to,N, N-dimethyl-para-toluidine (DMPT),N-(2-hydroxyethyl)-N-methyl-para-toluidine (MHPT), or combinationsthereof. Illustrative accelerators of the cure promoter composition canalso include, but are not limited to those cure promoters capable ofpromoting the cure of sealant material and form a network within theoptional gelling agent component during an initial synthesis, such asprior to packaging in a container. Illustrative accelerators of the curepromoter composition can also include, but are not limited tothiocarbamates, hydrated thiocarbamates, dithiocarbamates, sulfides,thiazoles, mercaptothiazoles, sulfenamides, thiazolesulfenamides,thiurams, thioureas, thiophosphates, metal salts of thiocarbamates,sulfur chloride, or combinations thereof. For example, the curepromoters can include thiuram, thiuram disulfide, tetrabenzylthiuramdisulfide such as WESTCO™ TBzTD, tetramethyl thiuram disulfide,tetraethyl thiuram disulfide (disulfiram), tetramethylthiurammonosulfide, dipentamethylene thiuram tetrasulfate, dipentaethylenethiuramelemental sulfur, tetraethyldisulfanedicarbothioamide,2,2-dithiobis(benzothiazole) (MBTS), MBT, ZMBT,N-tert-butyl-2-benzothiazole sulfenamide (TBBS), CBS, MIBS, DCBS,Zn-dibenzyldithiocarbamate (ZDBC), ZDEC, ZMDC, ethylene thiourea (ETU),dibutylthiourea (DBTU), Zn—O,O-di-N-phosphorodithioate (ZBDP) or thelike, or combinations thereof.

The one or more accelerator can be present in an amount of from about0.01 weight % to about 10 weight %, based on a total weight of the curepromoter composition. For example, the one or more accelerators can bepresent in an amount of from about 0.1 weight %, about 0.5 weight %,about 1 weight %, about 1.5 weight %, about 2 weight %, about 3 weight%, about 4 weight %, or about 5 weight % to about 6 weight %, about 6.5weight %, about 7 weight %, about 8 weight %, about 9 weight %, or about10 weight %, based on a total weight of the cure promoter composition.In another example, the one or more accelerators can be present in anamount of from about 0.1 weight % to about 10 weight %, about 2 weight %to about 8 weight %, or about 4 weight % to about 6 weight %.

The cure promoter composition can include one or more initiators, and/orcoinitiators. As used herein, the term or expression “initiator” or“coinitiator” can refer to any component, compound, or substance thatfacilitates or promotes the polymerization and/or cross-linking of asealant and/or between the one or more optional acrylates of the curepromoter composition.

The cure promoter composition can include one or more compatibilizingcarriers. As used herein, the term “compatibilizing carriers” can referto any component, compound, or substance that can dissolve theaccelerator and is soluble in the organic solvent and the sealant andfacilitates or promotes the migration or diffusion of the cure promotercomposition into a sealant material.

A compatibilizing carrier may also include monomers, oligomers, lowmolecular weight polysulfides, low molecular weight polythiols, orcombinations thereof. Illustrative compatibilizing carriers of the curepromoter composition can be or include, but are not limited to, includemonomers, oligomers, low molecular weight polysulfides, or combinationsthereof. For example, the cure promoters can include polythiols, andorganic solvents which may have allyl, vinyl, acrylate and methacrylatefunctional groups, including allyl monosulfide, allyl disulfide, ethylvinyl sulfide, phenyl vinyl sulfide, thiol-ene, multi-vinyl compounds,and combinations thereof. Illustrative compatibilizing carriers mayinclude pentaerythritol tetrakis(3-mercaptopropionate),trimethylolpropane tris(3-mercaptopropionate), 2,2′-thiodiethanethiol,1,4-butanedithiol, 2,2′-(ethylenedioxy)diethanethiol,tris(mercaptoalkyl) cyclohexanes, styrene, vinyl-functional silanes,Thiokol™ liquid polymer polysulfide, and combinations thereof.

The one or more compatibilizing carriers can be present in an amount offrom about 0.01 weight % to about 50 weight %, based on a total weightof the cure promoter composition. For example, the one or more curepromoters can be present in an amount of from about 0.1 weight %, about0.5 weight %, about 1 weight %, about 1.5 weight %, about 2 weight %,about 3 weight %, about 4 weight %, or about 5 weight % to about 6weight %, about 6.5 weight %, about 7 weight %, about 8 weight %, about9 weight %, or about 10 weight %, based on a total weight of the curepromoter composition. In another example, the one or morecompatibilizing carriers can be present in an amount of from about 0.1weight % to about 20 weight %, about 2 weight % to about 15 weight %, orabout 4 weight % to about 10 weight %.

The one or more adhesion promoters can be or include, but are notlimited to, one or more compounds including at least one reactivesilane, or organometallics including reactive titanate, reactivezirconate, reactive aluminates, or the like, or any combination thereof.Organosilanes are generally understood to be, but not necessarilylimited to, multifunctional silicon-containing molecules that include areactive functional group and one or more hydrolysable alkoxy group.Illustrative silanes can include, but are not limited to,bis(trimethoxysilylethyl)benzene, bis(triethoxysilylethyl)benzene,3-Acryloxypropyltrimethoxysilane, 3-Methacryloxypropyltrimethoxysilane,aminopropyltrimethoxysilane, vinyl trimethoxysilane, allyltrimethoxysilane, mercaptopropyltrialkoxysilanes (such asmercaptopropyltrimethoxysilanes 3-Mercaptopropyltrimethoxysilane), orcombinations thereof. Illustrative glycidoxy functional or epoxyfunctional silanes may include, but are not limited to,glycidoxypropyltrialkoxysilane (such asglycidoxypropyltrimethoxysilanes, 3-glycidoxypropyltrimethoxysilane,3-glycidoxypropyltriethoxysilane, and the like),3-(2,3-epoxypropoxypropyl)methyldiethoxysilane,2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane,3-(2,3-epoxypropoxypropyl)methyldimethoxysilane,2-(3,4-Epoxycyclohexyl)ethylmethyldimethoxysilane, and combinationsthereof. Illustrative mercapto functional silanes may include, but arenot limited to, 3-mercaptopropyltriethoxysilane,3-mercaptopropyltrimethoxysilane, 11-mercaptoundecyltrimethoxysilane,s-(octanoyl)mercaptopropyltriethoxysilane,(mercaptomethyl)methyldiethoxysilane,3-mercaptopropylmethyldimethoxysilane, and combinations thereof.

Organometallics included in the cure promoter composition may includereactive titanate, reactive zirconate, reactive aluminates, or the like,or any combination thereof. Organometallic compounds are generallyunderstood to be any member of a class of compounds containing at leastone metal-to-carbon bond in which the carbon is part of an organicgroup. Organometallic compounds of the present disclosure may furtherinclude metal centers including metals such as, but not limited to,manganese (Mn), lithium (Li), magnesium (Mg), aluminum (Al), zinc (Zn),and iron (Fe). The metal centers may have, but are not limited to, fromfour to six organic ligands or reactive groups in the organometalliccomposition. The organometallics may have, but are not limited to,reactive groups or organic ligands including amines, vinyl groups, allylether groups, acrylic groups, or combinations thereof. Theorganometallics may have, but are not limited to, non-reactive groupsincluding alkyl, alkoxy, fluoro, phosphates, or combinations thereof.The reactive titanates can, but are not required to, include at leastone UV curable functional group, such as an acrylate functional group.The UV curable functional group allows the titanate adhesion promoter tocure or facilitate curing via exposure to UV. The titanate adhesionpromoter can include an ethylenically unsaturated titanate containingcompound, a neoalkoxy titanate containing compound, or combinationsthereof. Illustrative titanate adhesion promoters can include, but arenot limited to, tetra (2, 2 diallyoxymethyl)butyl,di(ditridecyl)phosphito titanate, commercially available as KR 55, fromKenrich Petrochemcials, Inc. (hereinafter “Kenrich”) of Bayonne, NJ;neopentyl(diallyl)oxy, trineodecanonyl titanatem, commercially availableas LICA 01 from Kenrich; neopentyl(diallyl)oxy,tri(dodecyl)benzene-sulfony titanate, commercially available as LICA 09from Kenrich; neopentyl(diallyl)oxy, tri(dioctyl)phosphato titanate,commercially available as LICA 12 from Kenrich; neopentyl(dially)oxy,tri(dioctyl)pyro-phosphato titanate, commercially available as LICA38from Kenrich; neopentyl(diallyl)oxy, tri(N-ethylenediamino)ethyltitanate, commercially available as LICA 44 from Kenrich;neopentyl(diallyl)oxy, tri(m-amino)phenyl titanate, commerciallyavailable as LICA 97 from Kenrich; neopentyl(diallyl)oxy, trihydroxycaproyl titanate, commercially available as LICA 99 from Kenrich; or thelike, or combinations thereof.

The reactive zirconates can, but are not required to, include at leastone UV curable functional group, such as a methylacrulate or an acrylatefunctional group. The zirconate adhesion promoters can include anethylenically unsaturated zirconium containing compound, a neoalkoxyzirconate containing compound, or combinations thereof. Illustrativezirconate adhesion promoters can be or include, but are not limited to,tetra (2,2 diallyloxymnethyl)butyl, di(ditridecyl)phosphito zirconate,commercially available as KZ 55 from Kenrich; neopentyl(diallyl)oxy,trineodecanoyl zirconate, commercially available as NZ 01 from Kenrich;neopentyl(diallyl)oxy, tri(dodecyl)benzene-sulfony zirconate,commercially available as NZ 09 from Kenrich; neopentyl(diallyl)oxy,tri(dioctyl)phosphato zirconate, commercially available as NZ 12 fromKenrich; neopentyl(diallyl)oxy, tri(dioctyl)pyro-phosphato zirconate,commercially available as NZ 38 from Kenrich; neopentyl(diallyl)oxy,tri(N-ethylenediamino)ethyl zirconate, commercially available as NZ 44from Kenrich; neopentyl(diallyl)oxy, tri(m-amino)phenyl zirconate,commercially available as NZ 97 from Kenrich; neopentyl(diallyl)oxy,trimethacryl zirconate, commercially available as NZ 33 from Kenrich;neopentyl(diallyl)oxy, triacryl zirconate, commercially available as NZ39 from Kenrich; dineopentyl(diallyl)oxy, diparamino benzoyl zirconate,commercially available as NZ 37 from Kenrich; dineopentyl(aiallyl)oxy,di(3-mercapto) propionic zirconate, commercially available as NZ 66Afrom Kenrich; or combinations thereof.

As discussed above, the one or more adhesion promoters can also be orinclude, but are not limited to, one or more sealants. As used herein,the term or expression “sealant” can refer to compositions that can havethe ability to resist atmospheric conditions such as moisture andtemperature and at least partially block transmission of materials suchas water, fuel, and other liquids and gases. It should be appreciatedthat sealants can have adhesive or curative properties. It shouldfurther be appreciated that the sealants can be generally identified by“Class,” as determined by their viscosity. The cure promoter compositioncan be combined with Class A sealants, Class B sealants, Class Csealants, or any combination thereof. Class A sealants can generallyhave a viscosity of from about 100 poise to about 400 poise, and cangenerally be suitable for application by brushing, injecting, orspraying. Class A sealants can have an application time of about 0.5hours to about 2 hours. Class B sealants can generally have a viscosityof from about 6000 to about 18000 poise, and can generally be suitablefor application by extrusion gun or spatula. Class B sealants can havean application time of about 0.5 hours to about 2 hours. Class Csealants can generally have a viscosity between that of a Class Asealant and a Class B sealant. For example, Class C sealants cangenerally have a viscosity of from about 1000 to about 4000 poise, andcan generally be suitable for faying surface or shim sealing, brushcoating, or wet installation. Class C sealants can have an applicationtime of about 2 hours to about 336 hours. Viscosity of the Class A,Class B, and Class C sealants can be measured by a cone and platerheometer (ASTM D4287) or Brookfield viscometer (ASTM D2196). In anexemplary implementation, the one or more adhesion promoters includes aClass A sealant.

Illustrative sealant adhesion promoters can be or include, but are notlimited to, one or more reactive silanes, one or more reactivetitanates, one or more reactive zirconates, or the like, or combinationsthereof.

The one or more adhesion promoters can be present in an amount of fromabout 0.01 weight % to about 25 weight %, based on a total weight of thecure promoter composition. For example, the one or more adhesionpromoters can be present in an amount of from about 0.01 weight %, about0.5 weight %, about 1 weight %, about 1.5 weight %, about 2 weight %, orabout 2.5 weight % to about 2.75 weight %, about 3 weight %, about 3.5weight %, about 4 weight %, about 4.5 weight %, or about 10.0 weight %,based on a total weight of the cure promoter composition. In anotherexample, the one or more adhesion promoters can be present in an amountof from about 0.01 weight % to about 10.0 weight %, about 10.0 weight %to about 25 weight %, about 1 weight % to about 8.0 weight %, about 2.0weight % to about 6.0 weight %, or about 5 weight %, based on a totalweight of the cure promoter composition.

The one or more organic solvents of the cure promoter composition can becapable of or configured to disperse, solubilize, solvate, or otherwisedissolve one or more substances or components of the cure promotercomposition. The one or more organic solvents of the cure promotercomposition can also be capable of or configured to disperse,solubilize, solvate, or otherwise dissolve one or more substances, suchas greases, oils, or debris, on surfaces contacted with the curepromoter composition. For example, the one or more organic solvents ofthe cure promoter composition can be capable of or configured todissolve the one or more accelerators, the one or more compatibilizingcarriers, the one or more catalysts, the one or more optional reducingagents, the one or more reactive silanes, the one or more reactiveorganometallics, the one or more optional gelling agents, the one ormore functional additives, or combinations thereof. The one or moreorganic solvents can also be capable of or configured to prepare asurface for subsequent treatment or application of a sealant. Forexample, the one or more organic solvents can be capable of orconfigured to at least partially provide a cleaning treatment of asurface that is to be treated with a sealant, such as a polysulfidesealant. It should be appreciated that any organic solvent capable of orconfigured to dissolve one or more components of the cure promotercomposition and/or prepare the surface for subsequent treatment orapplication of a sealant can be utilized.

The one or more organic solvents can be or include, but are not limitedto, aliphatic hydrocarbons, aromatic compounds, such as aromatichydrocarbons, halogenated hydrocarbons, nitrated hydrocarbons, ketones,amines, esters, alcohols, aldehydes, ethers, or the like, orcombinations thereof.

Illustrative aliphatic hydrocarbons that can be utilized as the one ormore organic solvents can be or include, but are not limited to,n-pentane, n-hexane, n-octane, n-nonane, n-decane, or homologuesthereof, 2,2,4-trimethyl pentane, or the like, or any combinationthereof.

Illustrative aromatic compounds that can be utilized as the one or moreorganic solvents can be or include, but are not limited to, cyclohexane,benzene, toluene, ethylebenzene, xylene, tetralin, hexafluoro xylene, orthe like, or any combination thereof.

Illustrative halogenated hydrocarbons that can be utilized as the one ormore organic solvents can be or include, but are not limited to,chloroform, methylene chloride, trichloro ethylene, dichloromethane, orthe like, or combinations thereof.

Illustrative ketone organic solvents can be or include, but are notlimited to, acetone, methyl ethyl ketone (MEK), diethyl ketone, methylpropyl ketone (MPK), dipropyl ketone, methyl isobutyl ketone (MIBK),cyclopentanone, cyclohexanone, methyl amyl ketone,n-methyl-2-pyrrolidone, diisobutyl ketone, acetophenone, or the like, orcombinations thereof.

Illustrative esters that can be utilized as the one or more organicsolvents can be or include, but are not limited to, methyl acetate,ethyl acetate, isopropyl acetate, n-butyl acetate, cellosolve acetate,or the like, or combinations thereof.

Illustrative alcohols that can be utilized as the one or more organicsolvents can be or include, but are not limited to, methanol, ethanol,n-propanol, i-propanol, n-butanol, i-butanol, s-butanol, n-amyl alcohol,i-amyl alcohol, cyclohexanol, n-octanol, ethanediol, diethylene glycol,1,2-propanediol, or the like, or combinations thereof.

Illustrative aldehydes that can be utilized as the one or more organicsolvents can be or include, but are not limited to, furfuraldehyde, orthe like.

Illustrative ethers that can be utilized as the one or more organicsolvents can be or include, but are not limited to, diethyl ether,diisopropyl ether, dibutyl ether, methyl tert butyl ether, 1,4-dioxane,tetrahydrofuran, oligomers of perfluoropolyethers, such as the GALDEN®line, which is commercially available from Solvay of Houston, TX, or thelike, or combinations thereof.

Certain embodiments of cure promoter compositions as described hereinmay have very different viscosities which may be tailored according totheir method of application. The amount of the one or more organicsolvents present in the cure promoter composition can vary widely, ormay include an optional gelling agent, both of which may directlyinfluence the viscosity of a cure promoter composition. For example, alow viscosity composition may not include an optional gelling agent andmay have a greater solvent composition. The low viscosity solventcompositions can be applied to a surface or between two substrates byway of brushing, airbrush spraying, spray gun, dropping, pouring,pipetting, wiping, and the like. The amount of the one or more organicsolvents present can be at least partially determined by a target ordesired viscosity of the cure promoter composition. The amount of theone or more organic solvents present in the cure promoter compositioncan be from about 75 weight % to about 99.5 weight %, based on a totalweight of the cure promoter composition. For example, the amount of theone or more organic solvents present in a lower viscosity cure promotercomposition can be from about 75 weight %, about 80 weight %, about 85weight % or about 90 weight % to about 95 weight %, about 98 weight %,about 99 weight %, or about 99.5 weight %, based on a total weight ofthe cure promoter composition. In another example, the amount of the oneor more organic solvents present in the cure promoter composition may befrom about 75 weight % to about 99.5 weight %, about 80 weight % toabout 99 weight %, about 85 weight % to about 95 weight %, or about 85weight % to about 90 weight %, based on a total weight of the curepromoter composition.

The cure promoter composition having a lower viscosity can have a shearviscosity of from about 0.01 Pa·s to about 10 Pa·s, at a temperature ofabout 25° C. For example, the adhesion promoter composition can have ashear viscosity of from about 0.01 Pa·s, about 2 Pa·s, about 4 Pa·s, orabout 5 Pa·s to about 6 Pa·s, about 8 Pa·s, about 9 Pa·s, or about 10Pa·s at a temperature of about 25° C. In another example, the curepromoter composition can have a shear viscosity of from about 0.01 Pa·sto about 10 Pa·s, about 2 Pa·s to about 8 Pa·s, or about 4 Pa·s to about6 Pa·s, at a temperature of about 25° C. The cure promoter compositioncan have a shear rate of about 0.1 Hz to about 100 Hz, at a temperatureof about 25° C. The cure promoter composition can have a viscosity ofabout 0.01 to about 10 Pa·s at a shear rate of about 0.1 to about 100sec⁻¹.

Certain embodiments of cure promoter compositions having a higherviscosity composition can include an optional gelling agent and may havea lower solvent composition as compared to a low viscosity cure promotercomposition. The high viscosity solvent compositions can be applied to asurface or between two substrates by way of via an extrusion gun,syringe, brushing, rolling, spreading, wiping, and the like, and besuitable for application to overhead or vertical surfaces withoutrunning or sagging. The amount of the one or more organic solventspresent can be at least partially determined by a target or desiredviscosity of the higher viscosity cure promoter composition. The amountof the one or more organic solvents present in the cure promotercomposition can be from about 25 weight % to about 95 weight %, based ona total weight of the cure promoter composition. For example, the amountof the one or more organic solvents present in the cure promotercomposition can be from about 25 weight %, about 30 weight %, about 40weight % or about 50 weight % to about 60 weight %, about 65 weight %,about 70 weight %, or about 75 weight %, based on a total weight of thecure promoter composition. In another example, the amount of the one ormore organic solvents present in the cure promoter composition may befrom about 45 weight % to about 85 weight %, about 45 weight % to about50 weight %, about 55 weight % to about 65 weight %, or about 80 weight% to about 95 weight %, based on a total weight of the cure promotercomposition.

The cure promoter composition having a higher viscosity can have a shearviscosity of from about 0.1 Pa·s to about 100 Pa·s, or from about 1.0Pa·s to about 20 Pa·s, at a temperature of about 25° C. For example, thecure promoter composition can have a shear viscosity of from about 2.5Pa·s, about 5 Pa·s, about 7.5 Pa·s, or about 10 Pa·s to about 15 Pa·s,about 20 Pa·s, about 30 Pa·s, or about 40 Pa·s at a temperature of about25° C. In another example, the cure promoter composition can have ashear viscosity of from about 2.5 Pa·s to about 40 Pa·s, about 5 Pa·s toabout 25 Pa·s, or about 10 Pa·s to about 20 Pa·s, at a temperature ofabout 25° C. The measurement of the cure promoter composition may beconducted at a shear rate of about 0.1 Hz to about 100 Hz, at atemperature of about 25° C. The cure promoter composition can have aviscosity of about 2.5 Pa·s to about 40 Pa·s measured at a shear rate ofabout 0.1 to about 100 sec-1. The one or more gelling agents, which maybe, but are not necessarily limited to acrylates, of the cure promotercomposition can be capable of or configured to form a network with oneanother. For example, the one or more acrylates can be capable of orconfigured to interact (e.g., bond) with one another to form anacrylate-based network, such as a cross-linked acrylate based network.In another example, the one or more acrylates can be capable of orconfigured to polymerize into a cross-linked network or mesh that canswell with the solvent to provide a spreadable cure promotercomposition. The one or more acrylates can be or include one or moremonomers and/or one or more oligomers. The one or more acrylates can beor include acrylate monomers having a functionality of two or greater.

Illustrative acrylates can be or include, but are not limited to, one ormore acrylates, methacrylates, diacrylates, triacrylates, polyacrylates,or the like, or combinations thereof. The one or more acrylates can alsobe or include, but are not limited to, Tetrahydrofurfuryl Methacrylate;Isodecyl Methacrylate; 2(2-Ethoxyethoxy) Ethylacrylate; StearylAcrylate; Tetrahydrofuryl Acrylate; Lauryl Methacrylate; StearylMethacrylate; Lauryl Acrylate; 2-Phenoxyethyl Acrylate; 2-PhenoxyethylMethacrylate; Glycidyl Methacrylate; Isodecyl Acrylate; IsobomylMethacrylate; Isooctyl Acrylate; Tridecyl Acrylate; TridecylMethacrylate; Caprolactone Acrylate; Ethoxylated Nonyl Phenol Acrylate;Isobomyl Acrylate; Propoxylated Allyl Methacrylate; Methoxy PolyethyleneGlycol Monomethacrylate; Polypropylene Glycol Monomethacrylate;Ethoxylated Nonyl Phenol Methacrylate; BetaCarboxyethyl Acrylate;Beta-Carboxyethyl Methacrylate; Octyl Acrylate; Decyl Acrylate; OctylMethacrylate; Decyl Methacrylate; Ethoxylated Alkylphenol Acrylate;Ethoxylated Alkylphenol Methacrylate; Ebecryl™ 111, an EpoxyMonoacrylate commercially available from by UCB Chemicals of Brussells,Belgium; Ebecryl™ CL1039 a urethane Monoacrylate commercially availablefrom UCB Chemicals; Hexadecyl Acrylate; Hexadecyl Methacrylate; BehenylAcrylate; Behenyl Methacrylate; Nonyl Phenol Propoxylate Monoacrylate,Nonyl Phenol Propoxylate Monomethacrylate; Polyethylene GlycolDimethacrylate; Polyethylene Glycol Diacrylate; Tetraethylene GlycolDiacrylate; Triethylene Glycol Diacrylate; Tripropylene GlycolDiacrylate; 1,3 Butylene Glycol Dimethacrylate; Ethoxylated Bisphenol ADimethacrylate; Ethoxylated Bisphenol A Diacrylate; CyclohexaneDimethanol Diacrylate; Cyclohexane Dimethanol Dimethacrylate;Polypropylene Glycol Diacrylate; Polypropylene Glycol Dimethacrylate;Polyethylene Glycol Diacrylate; Polyethylene Glycol Dimethacrylate; 1,6Hexane Diol Diacrylate; 1,6 Hexane Diol Dimethacrylate; PropoxylatedNeopentyl Glycol Diacrylate; Propoxylated Neopentyl GlycolDimethacrylate; Ethoxylated Neopentyl Glycol Diacrylate; EthoxylatedNeopentyl Glycol Dimethacrylate; SR 9209, Alkoxylated AliphaticDiacrylate commercially available from Sartomer of Exton, PA;Dipropylene Glycol Diacrylate; Dipropylene Glycol Dimethacrylate;Tripropylene Glycol Dimethacrylate; Ebecryl™ 150, a Bisphenol Aderivative diacrylate commercially available from UCB Chemicals;Trimethylolpropane Trimethacrylate; Trimethylolpropane Triacrylate; Tris(2-Hydroxy Ethyl) Isocyanurate Triacrylate; Tris (2-Hydroxy Ethyl)Isocyanurate Trimethacrylate; Ethoxylated TrimethylolpropaneTriacrylate; Propoxylated Trimethylolpropane Triacrylate; EthoxylatedTrimethylolpropane Trimethacrylate; Propoxylated TrimethylolpropaneTrimethacrylate; Pentaerythritol Triacrylate; PentaerythritolTrimethacrylate; Propoxylated Glyceryl Triacrylate; PropoxylatedGlyceryl Trimethacrylate; Ethoxylated Glyceryl Triacrylate; EthoxylatedGlyceryl Trimethacrylate; Pentaerythritol Tetraacrylate;Di-Trimethylolpropane Tetraacrylate; Dipentaerythritol Pentaacrylate;Ethoxylated Pentaerythritol Tetraacrylate; SR 9041, a pentaacrylateEster commercially available from Sartomer; SR 9008, an AlkoxylatedTrifunctional Acrylate Ester commercially available from Sartomer; CD9009, a trifunctional Methacrylate Ester commercially available fromSartomer; SR 9012, a trifunctional Acrylate Ester commercially availablefrom Sartomer; CD 9050, a Monofunctional Acid Ester commerciallyavailable from Sartomer; CD 9051, a Trifunctional Acid Estercommercially available from Sartomer; SR 802, an Alkoxylated Diacrylatecommercially available from Sartomer; SR 500 Trifunctional monomercommercially available from Sartomer; SR 515 Trifunctional monomercommercially available from Sartomer; SR 516 Difunctional monomercommercially available from Sartomer; SR 517 Trifunctional monomercommercially available from Sartomer; SR 518 Tetrafunctional monomercommercially available from Sartomer; SR 519 Trifunctional monomercommercially available from Sartomer; SR521 Difunctional monomercommercially available from Sartomer; SR63 3 Metallic Diacrylatecommercially available from Sartomer; SR634 Metallic Dimethacrylatecommercially available from Sartomer; SR 636 Metallic Diacrylatecommercially available from Sartomer; SR 705 Metallic Diacrylatecommercially available from Sartomer; SR 708, Metallic Dimethacrylatecommercially available from Sartomer; SR 709, metallic Monomethacrylatecommercially available from Sartomer; CN 934, Urethane Acrylatecommercially available from Sartomer; CN 945, Trifunctional UrethaneAcrylate commercially available from Sartomer; CN95 3, Urethane Acrylatecommercially available from Sartomer; CN 961, Urethane Acrylatecommercially available from Sartomer; CN 962, Urethane Acrylatecommercially available from Sartomer; CN 963, Urethane Acrylatecommercially available from Sartomer; CN 964, Urethane Acrylatecommercially available from Sartomer; CN 965, Urethane Acrylatecommercially available from Sartomer; CN 966, Urethane Acrylatecommercially available from Sartomer; CN 980, Urethane Acrylatecommercially available from Sartomer; CN 198, Urethane Acrylatecommercially available from Sartomer; CN 982, Urethane Acrylatecommercially available from Sartomer; CN 983, Urethane Acrylatecommercially available from Sartomer; CN 984 Urethane Acrylatecommercially available from Sartomer; CN 985, Urethane Acrylatecommercially available from Sartomer; CN 986, Urethane Acrylatecommercially available from Sartomer; CN 970, Urethane Acrylatecommercially available from Sartomer; CN 971, Urethane Acrylatecommercially available from Sartomer; CN 972, Urethane Acrylatecommercially available from Sartomer; CN 973, Urethane Acrylatecommercially available from Sartomer; CN 975, Hexafunctional UrethaneAcrylate commercially available from Sartomer; CN 977, Urethane Acrylatecommercially available from Sartomer; CN 978, Urethane Acrylatecommercially available from Sartomer; CN 1 963, Urethane Methacrylatecommercially available from Sartomer; CN 104, Epoxy Acrylatecommercially available from Sartomer; CN 111, Epoxidized Soy Bean OilAcrylate commercially available from Sartomer; CN 112, Epoxy NovolakAcrylate commercially available from Sartomer; CN 115, Modified EpoxyAcrylate commercially available from Sartomer; CN 117, Modified EpoxyAcrylate commercially available from Sartomer; CN 118, Acid modifiedEpoxy Acrylate commercially available from Sartomer; CN120 EpoxyAcrylate commercially available from Sartomer; CN 124, Epoxy Acrylatecommercially available from Sartomer; CN 151, Epoxy Methacrylatecommercially available from Sartomer; CN 130, Aliphatic Monoacrylatecommercially available from Sartomer; CN 131, Aromatic Monoacrylatecommercially available from Sartomer; CN 132, Aliphatic Diacrylatecommercially available from Sartomer; CN 920, Polyester Acrylatecommercially available from Sartomer; CN 704, Acrylated Polyestercommercially available from Sartomer; CN 301, PolybutadieneDimethacrylate commercially available from Sartomer; SB 400,401,402,500,510, 520, Aromatic Acid Methacrylate commercially available fromSartomer; Ebecryl™ 745, Acrylated Acrylic commercially available fromUCB Chemicals; Ebecryl™ 754 Acrylated Acrylic commercially availablefrom UCB Chemicals; Ebecryl™ 1701 Acrylated Acrylic commerciallyavailable from UCB Chemicals; Ebecryl™ 1710 AcrylatedAcryliccommercially available from UCB Chemicals; Ebecryl™ 1755 AcrylatedAcrylic commercially available from UCB Chemicals; Ebecryl™ 230Acrylated Urethane commercially available from UCB Chemicals; Ebecryl™244, Acrylated Urethane commercially available from UCB Chemicals;Ebecryl™ 264 Acrylated Urethane commercially available from UCBChemicals; Ebecryl™ 270 Acrylated Urethane commercially available fromUCB Chemicals; Ebecryl™ 284 Acrylated Urethane commercially availablefrom UCB Chemicals; Ebecryl™ 1290 Acrylated Urethane commerciallyavailable from UCB Chemicals; Ebecryl™ 2001 Acrylated Urethanecommercially available from UCB Chemicals; Ebecryl™ 4830 AcrylatedUrethane commercially available from UCB Chemicals; Ebecryl™ 4833Acrylated Urethane commercially available from UCB Chemicals; Ebecryl™4835 Acrylated Urethane commercially available from UCB Chemicals;Ebecryl™ 4842 Acrylated Urethane commercially available from UCBChemicals; Ebecryl™ 4866 Acrylated Urethane commercially available fromUCB Chemicals; Ebecryl™ 4883 Acrylated Urethane commercially availablefrom UCB Chemicals; Ebecryl™ 5129 Acrylated Urethane commerciallyavailable from UCB Chemicals; Ebecryl™ 8301 Acrylated Urethanecommercially available from UCB Chemicals; Ebecryl™ 8402 AcrylatedUrethane commercially available from UCB Chemicals; Ebecryl™ 8800Acrylated Urethane commercially available from UCB Chemicals; Ebecryl™8803 Acrylated Urethane commercially available from UCB Chemicals;Ebecryl™ 8804 Acrylated Urethane commercially available from UCBChemicals; Ebecryl™ 8807 Acrylated Urethane commercially available fromUCB Chemicals; Ebecryl™ 3604 Rubber modified Epoxy Acrylate commerciallyavailable from UCB Chemicals; Ebecryl™ 3605 Acrylated Bisphenol A Epoxycommercially available from UCB Chemicals; Ebecryl™ 3702 Fatty AcidModified Epoxy Acrylate commercially available from UCB Chemicals;Ebecryl™ 3703 Amine Modified Bisphenol A Acrylate commercially availablefrom UCB Chemicals; Ebecryl™ 3411 Fatty Acid Modified Epoxy Acrylatecommercially available from UCB Chemicals; Ebecryl™ 3600 Amine ModifiedBisphenol A Acrylate commercially available from UCB Chemicals; Ebecryl™168 Methacrylated Acidic Monomer commercially available from UCBChemicals; Ebecryl™ 170 Acrylated acidic monomer commercially availablefrom UCB Chemicals; Ebecryl™ 350 Acrylated Silicone commerciallyavailable from UCB Chemicals; Ebecryl™ 1360 Silicone Hexaacrylatecommercially available from UCB Chemicals; Genomer™ 4188 UrethaneAcrylate commercially available from Rahn; Genomer™ 4205 UrethaneAcrylate commercially available from Rahn; Genomer™ 4215 UrethaneAcrylate commercially available from Rahn; Genomer™ 4246 UrethaneAcrylate commercially available from Rahn; Genomer™ 4269 UrethaneAcrylate commercially available from Rahn; Genomer™ 4297 UrethaneAcrylate commercially available from Rahn; Genomer™ 4302 UrethaneAcrylate commercially available from Rahn; Genomer™ 4312 UrethaneAcrylate commercially available from Rahn; Genomer™ 4316 UrethaneAcrylate commercially available from Rahn; Genomer™ 4510 UrethaneAcrylate commercially available from Rahn; Genomer™ 4661 UrethaneAcrylate commercially available from Rahn; Genomer™ 4205 UrethaneAcrylate commercially available from Rahn; Genomer™ 5248 UrethaneAcrylate commercially available from Rahn; Genomer™ 5275 UrethaneAcrylate commercially available from Rahn; Genomer™ 5695 UrethaneAcrylate commercially available from Rahn; Genomer™ 7154 UrethaneAcrylate commercially available from Rahn; Photomer® 5018, polyesteracrylate commercially available from Photomer Energy Curing Chemicals;Photomer® 5018, polyester acrylate commercially available from PhotomerEnergy Curing Chemicals; RCC™ 13-429, polyester acrylate commerciallyavailable from Photomer Energy Curing Chemicals; RCC™ 13-430, polyesteracrylate commercially available from Photomer Energy Curing Chemicals;RCC™ 13-432, polyester acrylate commercially available from PhotomerEnergy Curing Chemicals; RCC™ 13-433, polyester acrylate commerciallyavailable from Photomer Energy Curing Chemicals; Photomer® 6008,Urethane Acrylate commercially available from Photomer Energy CuringChemicals; Photomer® 6010, Urethane Acrylate commercially available fromPhotomer Energy Curing Chemicals; Photomer® 6022, Urethane Acrylatecommercially available from Photomer Energy Curing Chemicals; Photomer®6184, Urethane Acrylate commercially available from Photomer EnergyCuring Chemicals; Photomer® 6210, Urethane Acrylate commerciallyavailable from Photomer Energy Curing Chemicals; Photomer® 6217,Urethane Acrylate commercially available from Photomer Energy CuringChemicals; Photomer® 6788-20R, Urethane Acrylate commercially availablefrom Photomer Energy Curing Chemicals; Photomer® 6893, Urethane Acrylatecommercially available from Photomer Energy Curing Chemicals; RCC™12-891, Urethane Acrylate commercially available from Photomer EnergyCuring Chemicals; RCC™ 12-892, Urethane Acrylate commercially availablefrom Photomer Energy Curing Chemicals; RCC™ 13-363, Urethane Acrylatecommercially available from Photomer Energy Curing Chemicals; Photomer®6173, Aromatic Acrylate commercially available from Photomer EnergyCuring Chemicals; RCC™ 13-424, Polyester Acrylate commercially availablefrom Photomer Energy Curing Chemicals. In an exemplary implementation,the one or more acrylates include polybutadiene dimethacrylate,pentaerythritol tetraacrylate, or the like, or combinations thereof.

The amount of the one or more acrylates present in the cure promotercomposition can vary widely. The amount of the one or more acrylatespresent can be at least partially determined by a target or desiredviscosity of the cure promoter composition. The amount of the one ormore acrylates present in the cure promoter composition can be fromabout 1 weight % to about 25 weight %, based on a total weight of thecure promoter composition. For example, the amount of the one or moreacrylates present in the cure promoter composition can be from about 1weight %, about 5 weight %, or about 10 weight % to about 15 weight %,about 20 weight %, or about 25 weight %, based on a total weight of thecure promoter composition. In another example, the amount of the one ormore acrylates present in the cure promoter composition can be fromabout 1 weight % to about 25 weight %, about 5 weight % to about 20weight %, or about 10 weight % to about 15 weight %.

The cure promoter composition can include one or more optionalfunctional additives capable of or configured to provide additionalfunctional properties to the cure promoter composition. The one or moreoptional functional additives can be or include, but are not limited to,one or more indicators (e.g., visual indicators), one or more abrasives,one or more plasticizers, one or more surfactants, one or more flameretardant agents, one or more biocides, one or more tackifiers capableof or configured to modify tack of the cure promoter composition, one ormore cure promoters, one or more accelerants, or the like, or anycombination thereof. Examples of optional functional additives referredto herein are discussed further in turn below. The optional functionaladditives may be combined with the cure promoter composition to add oneor more functionalities alone or in combination with other additives forfurther functionalities.

The cure promoter composition can include one or more catalysts. As usedherein, the term “catalyst” can refer to any component, compound, orsubstance that can increase the rate of a chemical reaction related tosealant crosslinking, without necessarily undergoing a permanentchemical change.

The catalyst can be or include, but is not limited to, one or moreamidines, diazoles, amines, pyridines, and combinations thereof.Illustrative catalysts can be or include, but are not limited to, one ormore azo compounds, such as 4,4′-azobis(4-cyanovaleric acid),1,1′-azobis(cyclohexanecarbonitrile), azobisisobutyronitrile,2,2′-azobis(2-methylpropionitrile), or2,2′-Azobis(2-methylpropionitrile), one or more inorganic peroxides,such as ammonium persulfate, hydroxymethanesulfinic acid monosodium saltdihydrate, potassium persulfate, or sodium persulfate, one or moreorganic peroxides, such as benzoyl peroxide, t-butyl hydroperoxide,cumene hydroperoxide, dicumyl peroxide, t-butyl peroxide, or the like,or any combination thereof. The illustrative catalysts can also be orinclude, but are not limited to, one or more organic photoinitiators,such as one or more acetophenone, one or more benzyl and benozoincompounds, one or more benzophenones, one or more cationicphotoinitiators, one or more thioxanthones, camphorquinone,1-methylimidazole, 2-(dimethylamino)ethyl methacrylate,1,8-diazabicyclo[5.4.0]undec-7-ene, pyridine, ethylenediaminetetraaceticacid (EDTA), or the like, or any combination thereof.

The one or more catalysts can be present in an amount of from about 0.1weight % to about 10 weight %, based on a total weight of the curepromoter composition. For example, the one or more catalysts can bepresent in an amount of from about 0.1 weight %, about 0.5 weight %,about 1 weight %, about 1.5 weight %, about 2 weight %, about 3 weight%, about 4 weight %, or about 5 weight % to about 6 weight %, about 6.5weight %, about 7 weight %, about 8 weight %, about 9 weight %, or about10 weight %, based on a total weight of the cure promoter composition.In another example, the one or more catalysts can be present in anamount of from about 0.1 weight % to about 5 weight %, about 0.5 weight% to about 2.5 weight %, or about 0.5 weight % to about 1.0 weight %.

The cure promoter composition can include one or more reducing agents.As used herein, the term “reducing” can refer to any component,compound, or substance that can lose or donate one or more electrons toan electron recipient or oxidizing agent. In the context of a curepromoter composition, as described herein, a reducing agent can reduce asulfide functional group or component included in the cure promotercomposition or sealant composition, or both, into a thiol functionalgroup.

Illustrative reducing agents can be or include, but are not limited to,cysteamine, betamercaptoethanol, dithiothreitol, tris(2-carboxyethyl)phosphine hydrochloride, dithiobutylamine, glutathione, tertiary amines,azo compounds, amine-functional silanes, or the like, or any combinationthereof. The illustrative reducing agents can also be or include, butare not limited to, one or more amine-functional reducing agents, suchas 1-methylimidazole, m-xylenediamine, 4, N, N-trimethyl aniline, or thelike, or any combination thereof.

The one or more reducing agents can be present in an amount of fromabout 0.1 weight % to about 10 weight %, based on a total weight of thecure promoter composition. For example, the one or more reducing agentscan be present in an amount of from about 0.1 weight %, about 0.5 weight%, about 1 weight %, about 1.5 weight %, about 2 weight %, about 3weight %, about 4 weight %, or about 5 weight % to about 6 weight %,about 6.5 weight %, about 7 weight %, about 8 weight %, about 9 weight%, or about 10 weight %, based on a total weight of the cure promotercomposition. In another example, the one or more reducing agents can bepresent in an amount of from about 0.1 weight % to about 10 weight %,about 2 weight % to about 8 weight %, or about 4 weight % to about 6weight %.

The cure promoter composition may include, but is not limited to, anaqueous component. An aqueous component contains water, and may include,but is not limited to, water soluble additives, other surfactants,minerals, salts, acids, bases, buffers, or combinations thereof. A wateror aqueous component included in the cure promoter composition mayparticipate or initiate a reaction in one or more of the othercomponents or the cure promoter composition, such as the one or morereactive silanes, the one or more reactive organometallics, the one ormore reducing agents, or combinations thereof. For example, thealkoxysilyl groups in a silane react with water to form silanol groups.These silanol groups may be unstable and over time will undergocondensation. A condensation reaction may result in the formation ofcrosslinking between silane molecules, as well as gelation. A adjustingthe pH of the aqueous component may improve the stability of thesesilanol groups. Meanwhile, amino silanes are very stable in aqueoussolutions, due to interaction of the amino groups. The water or aqueouscomponent may also dissolve or solubilize one or more components oradditives included in the cure promoter composition.

The aqueous component can be present in an amount of from about 0.1weight % to about 10 weight %, based on a total weight of the curepromoter composition. For example, the aqueous component can be presentin an amount of from about 0.1 weight %, about 0.5 weight %, about 1weight %, about 1.5 weight %, about 2 weight %, about 3 weight %, about4 weight %, or about 5 weight % to about 6 weight %, about 6.5 weight %,about 7 weight %, about 8 weight %, about 9 weight %, or about 10 weight%, based on a total weight of the cure promoter composition. In anotherexample, the aqueous component can be present in an amount of from about0.1 weight % to about 10 weight %, about 2 weight % to about 8 weight %,or about 4 weight % to about 6 weight %.

The one or more indicators or visual indicators can be capable of orconfigured to facilitate, promote, or provide identification of an areaor surface treated with the cure promoter composition. For example, thevisual indicators can be capable of or configured to allow a user toidentify what surfaces or areas have been treated by the cure promotercomposition in varying environments (e.g., low light, confined space,etc.). The one or more indicators can be or include, but are not limitedto, one or more dyes, pigments, ultraviolet (UV) indicators, or thelike, or combinations thereof. The one or more indicators can be visiblein the visible spectrum (wavelength of 380 nm to 700 nm), the UVspectrum (wavelength of 10 nm to 380 nm), or combinations thereof. Theone or more indicators can absorb in the UV spectrum and emit in thevisible spectrum. Said in another way, the visual indicator can absorbenergy in the ultraviolet spectrum, and the visual indicator can emitenergy in the visible spectrum. The one or more indicators can includeone or more fluorescent compounds, phosphorescent compounds, orcombinations thereof.

Illustrative indicators can be or include, but are not limited to, aproprietary blend of Chromate(2-),[4-[(5-chloro-2-hydroxy-3-nitrophenyl)azo]-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)][3-[[1-(3-chlorophenyl)-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-4-yl]azo]-4-hydroxy-5-nitrobenzenesulfonato(3-)]-,disodium, 1-methoxy-2-propanol, 1,2-propanediol, and 2-methoxypropanol,a crimson red solvent based red liquid dye commercially available fromKEDA™ Dye of Manitowoc, WI, Triple Glow Powder commercially availablefrom GLONATION of Falmouth, KY, or the like, or combinations thereof.

The one or more indicators can be present in an amount of from about0.01 weight % to about 5 weight %, based on a total weight of the curepromoter composition. For example, the one or more indicators can bepresent in an amount of from about 0.01 weight %, about 0.05 weight %,about 0.1 weight %, about 0.5 weight %, about 1 weight %, about 2 weight%, or about 2.5 weight % to about 3 weight %, about 3.5 weight %, about4 weight %, about 4.5 weight %, or about 5 weight %, based on a totalweight of the cure promoter composition. In another example, the one ormore indicators can be present in an amount of from about 0.01 weight %to about 5 weight %, about 2 weight % to about 4 weight %, or about 3weight % to about 3.5 weight %, based on a total weight of the curepromoter composition.

The cure promoter composition can include one or more abrasives. As usedherein, the term “abrasive” can also refer to materials commonlyreferred to as “polishing agents.” The one or more abrasives can becapable of or configured to roughen the surface to facilitate, improve,or otherwise aid adhesion. The one or more abrasives can also be capableof or configured to roughen the surface to facilitate, improve, orotherwise aid adhesion, diffusion, migration, or contact of a surface incombination with cure promoter chemistry. The one or more abrasives canalso be capable of or configured to facilitate, improve, or otherwiseaid in the removal of debris and/or residue from the surface.

Illustrative abrasives of the cure promoter composition can be orinclude, but are not limited to, silica, alumina, hydrated alumina,silicates (e.g., zirconium silicate, aluminum silicate includingcalcined aluminum silicate), talc, sand, glass particles,aluminosilicates, barium sulfate, mica, diatomites, calcium carbonate,calcium sulfate, carbon, wollastonite, metaphosphate compounds,phosphate salts (e.g., insoluble phosphate salts), such as sodiummetaphosphate, potassium metaphosphate, calcium pyrophosphate, magnesiumorthophosphate, trimagnesium orthophosphate, tricalcium phosphate,dicalcium phosphate dihydrate, anhydrous dicalcium phosphate, calciumcarbonate, magnesium carbonate, or the like, or combinations thereof.

The one or more abrasives can be present in an amount of from about 0.1weight % to about 10 weight %, based on a total weight of the curepromoter composition. For example, the one or more abrasives can bepresent in an amount of from about 0.1 weight %, about 0.5 weight %,about 1 weight %, about 1.5 weight %, about 2 weight %, about 3 weight%, about 4 weight %, or about 5 weight % to about 6 weight %, about 6.5weight %, about 7 weight %, about 8 weight %, about 9 weight %, or about10 weight %, based on a total weight of the cure promoter composition.In another example, the one or more abrasives can be present in anamount of from about 0.1 weight % to about 10 weight %, about 2 weight %to about 8 weight %, or about 4 weight % to about 6 weight %.

The cure promoter composition can include one or more plasticizers. Asused herein, the term “plasticizer” can refer to any component,compound, or substance that can facilitate, produce, or promoteplasticity and flexibility and/or reduce brittleness. As such, one ormore plasticizers can be incorporated to modify (e.g., increase ordecrease) plasticity, flexibility, and/or brittleness of the curepromoter composition.

The one or more plasticizers can be present in an amount of from about0.1 weight % to about 10 weight %, based on a total weight of the curepromoter composition. For example, the one or more plasticizers can bepresent in an amount of from about 0.1 weight %, about 0.5 weight %,about 1 weight %, about 1.5 weight %, about 2 weight %, about 3 weight%, about 4 weight %, or about 5 weight % to about 6 weight %, about 6.5weight %, about 7 weight %, about 8 weight %, about 9 weight %, or about10 weight %, based on a total weight of the cure promoter composition.In another example, the one or more plasticizers can be present in anamount of from about 0.1 weight % to about 10 weight %, about 2 weight %to about 8 weight %, or about 4 weight % to about 6 weight %.

The cure promoter composition can include one or more surfactants. Asused herein, the term “surfactant” can refer to any component, compound,or substance that reduces surface tension in a solution or reducesinterfacial tension between two liquids, or between a liquid and asolid. The one or more surfactants can be capable of or configured tofacilitate or aid in the cleaning the surface of oil and/or debris. Theone or more surfactants can be capable of or configured to facilitatemigration or diffusion of one or more components of the cure promotercomposition into the bulk of a sealant or coating layer. The one or moresurfactants can be capable of or configured to better disperse any oneor more components, particulates, or elements of the adhesion promotercomposition with another one or more components, particulates, orelements of the adhesion promoter composition. In an exemplaryimplementation, the cure promoter composition includes at least onenonionic surfactant.

The one or more surfactants can be or include one or more anionicsurfactants, one or more amphoteric surfactants, one or more cationicsurfactants, one or more zwitterionic surfactants, one or more nonionicsurfactants, or mixtures thereof. Illustrative surfactants of the curepromoter composition can be or include, but are not limited to, ionicsurfactants and/or nonionic surfactants including octylphenoxypolyethoxy ethanols, such as TRITON™ X-100, X-114, and X-405,commercially available from Union Carbide Co. of Danbury, CT.

The one or more surfactants can be present in an amount of from about0.1 weight % to about 10 weight %, based on a total weight of the curepromoter composition. For example, the one or more surfactants can bepresent in an amount of from about 0.1 weight %, about 0.5 weight %,about 1 weight %, about 1.5 weight %, about 2 weight %, about 3 weight%, about 4 weight %, or about 5 weight % to about 6 weight %, about 6.5weight %, about 7 weight %, about 8 weight %, about 9 weight %, or about10 weight %, based on a total weight of the cure promoter composition.In another example, the one or more surfactants can be present in anamount of from about 0.1 weight % to about 10 weight %, about 2 weight %to about 8 weight %, or about 4 weight % to about 6 weight %.

The cure promoter composition can include one or more flame retardantagents. As used herein, the term “flame retardant agents” can refer toany component, compound, or substance that reduces, slows, or otherwisestops the spread and/or intensity of a fire. The one or more flameretardant agents can be capable of or configured to provide flameretardant properties to the cure promoter composition.

Illustrative flame retardant agents of the cure promoter composition canbe or include, but are not limited to, halogenated species orphosphorous containing species, or the like, or combinations thereof.

The one or more flame retardant agents can be present in an amount offrom about 0.1 weight % to about 10 weight %, based on a total weight ofthe cure promoter composition. For example, the one or more flameretardant agents can be present in an amount of from about 0.1 weight %,about 0.5 weight %, about 1 weight %, about 1.5 weight %, about 2 weight%, about 3 weight %, about 4 weight %, or about 5 weight % to about 6weight %, about 6.5 weight %, about 7 weight %, about 8 weight %, about9 weight %, or about 10 weight %, based on a total weight of the curepromoter composition. In another example, the one or more flameretardant agents can be present in an amount of from about 0.1 weight %to about 10 weight %, about 2 weight % to about 8 weight %, or about 4weight % to about 6 weight %.

The cure promoter composition can include one or more biocides. As usedherein, the term “biocides” can refer to any component, compound, orsubstance that kills or inhibits the growth of microorganisms such asbacteria, molds, slimes, fungi, or the like, or any combination thereof.

Illustrative biocides of the cure promoter composition can be orinclude, but are not limited to, chlorinated hydrocarbons,organometallics, halogen-releasing compounds, metallic salts, organicsulfur compounds, quaternary ammonium compounds, phenolics, or the like,or combinations thereof.

The one or more biocides can be present in an amount of from about 0.1weight % to about 10 weight %, based on a total weight of the curepromoter composition. For example, the one or more biocides can bepresent in an amount of from about 0.1 weight %, about 0.5 weight %,about 1 weight %, about 1.5 weight %, about 2 weight %, about 3 weight%, about 4 weight %, or about 5 weight % to about 6 weight %, about 6.5weight %, about 7 weight %, about 8 weight %, about 9 weight %, or about10 weight %, based on a total weight of the adhesion promotercomposition. In another example, the one or more biocides can be presentin an amount of from about 0.1 weight % to about 10 weight %, about 2weight % to about 8 weight %, or about 4 weight % to about 6 weight %.

Methods for preparing any one or more of the cure promoter compositionsdisclosed herein are provided. The method can include combining, mixing,blending, or otherwise contacting the one or more accelerators, the oneor more compatibilizing carriers, the one or more catalysts, theoptional one or more reducing agents, the one or more organic solvents,the one or more reactive silanes, the one or more reactiveorganometallics, the optional one or more gelling agents or acrylates,and/or the one or more optional functional additives (e.g., indicators,abrasives, plasticizers, surfactants, flame retardant agents, and/orbiocides) with one another to prepare a mixture. It should beappreciated that the order of mixing or contacting each of thecomponents of the cure promoter composition can be at least partiallydetermined by the specific components selected. The method can alsoinclude purging the mixture with nitrogen to remove dissolved oxygen.The method can further include combining, mixing, blending, or otherwisecontacting the mixture with one or more initiators and/or coinitiators.The method can also include forming a network between the one or moregelling agent acrylates. For example, the method can also includepolymerizing and/or cross-linking the one or more acrylates of themixture to prepare the one or more optional gelling agents of the curepromoter composition. It should be appreciated that alternatively, anyof the other components of the cure promoter composition can be addedbefore and/or after polymerizing and/or cross-linking the one or moreacrylates of the mixture. The polymerization and/or cross-linking of theone or more acrylates can be performed at room temperature and/or withadded heat. The method can also include exposing the mixture, includinga photoinitiator, to predetermined wavelengths of light to promotepolymerization and/or cross-linking. It should be noted that inembodiments as described herein, a gelled component may be fabricatedseparately and added to a cure promoter composition for the purpose ofviscosity modification.

The method can also include subjecting the cure promoter composition toviscosity modification. For example, the method can include homogenizingthe cure promoter composition via shearing and/or dicing in anindustrial blender, immersion blender, centrifugal mixer, or the like,or any combination thereof. The cure promoter composition can besubjected to viscosity modification for a period of from about 5 seconds(sec), about 10 sec, about 30 sec, or about 1 min to about 2 min, about3 min, about 5 min, about 10 min, about 30 min, or greater. The methodcan include adding additional organic solvents to the cure promoterprior to homogenizing the cure promoter composition. The cure promotercomposition can be homogenized, for example, in a centrifugal mixer, inthe presence of one or more particles. Illustrative particles can be orinclude, but are not limited to, one or more glass particles, ceramicparticles, or the like, or any combination thereof.

The method can further include separating the one or more particlesand/or relatively larger adhesion promoter agglomerations from the curepromoter composition after homogenization. For example, the method caninclude separating the particles and/or relatively larger adhesionpromoter agglomerations from the adhesion promoter composition viafiltration. Filtration can include passing the cure promoter compositionincluding the one or more particles (e.g., glass particles) and/or therelatively larger adhesion promoter agglomerations through a filterhaving a pore size less than about 1 mm, less than about 0.5 mm, lessthan about 0.25 mm, or less than about 0.1 mm.

Methods for utilizing any one or more of the cure promoter compositionsdisclosed herein to treat an uncured sealant surface after the sealantis applied to a substrate are provided. The substrate can be any surfaceto be treated with a sealant. Surfaces or substrates may include, butare not limited to aluminum, titanium, carbon fiber composites, carbonfiber reinforced composites, thermoplastics, or combinations thereof.For example, the surface can be a surface of a bridge truss, supportcolumn, construction object, building, vehicle, such as an atmosphericvehicle, an aerospace vehicle, an unmanned vehicle, an aircraft, aspacecraft, a satellite, a rocket, a missile, or the like, or anycomponents thereof.

The method for utilizing the cure promoter composition can includeapplying or contacting the cure promoter composition with the surface ofan uncured sealant. The cure promoter composition can be contacted withthe surface via a brush, a roller, an extrusion gun, a spray gun, or thelike, or any combination thereof. The cure promoter composition can becapable of or configured to improve the efficiency of or eliminate oneor more steps in the conventional process or method of preparing asurface for the application of a sealant. For example, in a conventionalprocess of applying a sealant to a substrate, the sealant may becombined with a curative, crosslinker or cure promoter. The curepromoter composition disclosed herein may be configured to concurrentlyor simultaneously migrate into the bulk material of a sealant layerhaving no combined curative in its composition and causing a curing orcrosslinking reaction within the sealant, thereby reducing the amount ofcurative needed for prior mixing of a sealant and potentially reducingsome amounts of materials or processing steps in the conventionalmethods of the application of a sealant.

The method for utilizing the cure promoter composition to cause a curingreaction within an uncured sealant can include a cure promotercomposition of one part or two parts. The method can further include aone-part cure promoter composition which is a combination of one or moreorganic solvents, a compatibilizing carrier, one or more optionalreactive silanes, one or more optional organometallics, one or moreoptional reducing agents, and a catalyst having a pre-determined shelflife. The method can further include a two-part cure promotercomposition that includes preparation by combining a first partincluding one or more organic solvents, a compatibilizing carrier, oneor more optional reactive silanes, one or more optional organometallics,and one or more optional reducing agents with a second part includingone or more organic solvents with a catalyst, which has a pre-determinedshelf life before and after combining the parts. The method can furtherinclude combining a two-part cure promoter composition immediately priorto use or application.

The method for utilizing the cure promoter composition to treat asurface of an uncured sealant can include evaporating the one or moreorganic solvents of the cure promoter composition. The method canfurther include activating the one or more reactive silanes or reactiveorganometallics of the adhesion promoter composition. The method canfurther include pausing after applying the cure promoter composition tothe sealant surface to allow the cure promoter time to react with thesealant or to migrate into the thickness of the sealant layer. Themethod can further include removing residual solvent or unreactedresidue of the cure promoter composition from the sealant surface byphysical wiping after activation. The method can also include filling aseal cap with a Class B sealant, disposing the seal cap, and applyingthe cure promoter adjacent or onto the sealant surface, and allowing thesealant to cure. The method can further include curing the Class Bsealant or applying the cure promoter composition to the surface of theClass B sealant, a resin, a paint layer, or a paint composition.Alternatively, a paint or primer may be applied onto the surface of thecured sealant, which has been treated with a surface application of thecure promoter. The method can also include filling a seal cap with athixotropic sealant and disposing the seal cap after the application ofthe cure promoter composition on the surface, followed by a secondapplication of cure promoter, thus exposing multiple surfaces of thesealant to an application of the cure promoter. Similarly, the methodcan also include extruding the thixotropic sealant on the aircraftstructure after application of the cure promoter composition on thesurface.

EXAMPLES

The examples and other implementations described herein are exemplaryand not intended to be limiting in describing the full scope ofcompositions and methods of this disclosure. Equivalent changes,modifications and variations of specific implementations, materials,compositions and methods can be made within the scope of the presentdisclosure, with substantially similar results.

Materials used in the following Examples were obtained as follows:Methyl ethyl ketone (MEK), Methyl propyl ketone (MPK), Allyl sulfide(AS), Pentaerythritol tetrakis(3-mercaptopropionate) (PTMP),Zinc-diethyldithiocarbamate (Zn-diS), Zinc-acetate dihydrate (Zn—H2O),Tetraethylthiuram disulfide (Disulfiram), 1-methylimidazole (Mel),(3-Glycidyloxypropyl)trimethoxysilane (GlycidylSilane), and(3-Mercaptopropyl)trimethoxysilane (MercaptoSilane) are all commerciallyavailable from SIGMA-ALDRICH® of St. Louis, MO. LICA 97 or Titanium IV2,2(bis 2-propenolatomethyl) butanolato, tris (3-amino) phenylato iscommercially available from Kenrich Petrochemicals, Bayonne, NJ.Thiokol™ LP3 (LP3) liquid polysulfide polymer was obtained from TorayFine Chemicals, Co., Ltd. and Polysulfide sealant Class B-2 WS8035 wasobtained from Royal Adhesives and Sealants of South Bend, IN.

Example 1

An exemplary series of cure promoter compositions was prepared as shownin Table 1 below. This set of samples in Example 1 illustrate thesynthesis of cure promoter solutions that when applied on uncuredsealant, Royal WS8035, would reduce the time to obtain a tack-freesurface. Each component is expressed in weight percent of the totalweight of the cure promoter composition. The accelerator was firstdissolved into solvent, then the dicumyl peroxide catalyst was stirredin if the recipe for the sample is so designated. The reducing agent, oramine was added last. The mixing can be done with a 10 gram scale vortexmixer, 100-500 g scale stir plate, or an overhead stirrer for samplesizes larger than 500 g. This solution was brushed or sprayed over anuncured sealant. The commercial sealant was prepared as instructed fromtechnical data sheet. The surface was tack free in less than an hourwith both samples 5 and 6 from Example 1.

TABLE 1 Surface Sample Reducing tack free # Accelerator Solvent CatalystAgent time 5 Disulfiram MEK/ — 1- <1 h 2.5% MPK Methylimidazole 95% 2.5%6 Disulfiram MEK/ Dicumyl 1- <1 h 2.5% MPK peroxide Methylimidazole 95%1% 2.5%

Example 2

Another exemplary series of cure promoter compositions was prepared asshown in Table 2 below. This set of samples in Example 2 illustrate thesynthesis of cure promoter solutions that when applied on uncuredsealant, Royal WS8035, would reduce the time to obtain a tack-freesurface. Each component is expressed in weight percent of the totalweight of the cure promoter composition. Various reducing agents, oramine compositions were utilized in the samples within Example 2, andwere prepared similarly to the procedures outlined in Example 1.

TABLE 2 Catalyst Surface Tack Sample # Accelerator Solvent (Peroxide)Reducing Agent Free Time 0 Control Sample >3 h 1 Disulfiram, MEK/MPK, —m-Xylylenediamine, <1 h 4.0% 95% 1% 2 Disulfiram, MEK/MPK, —4,N,N-Trimethyl <1 h 4.0% 95% aniline, 1% 3 Disulfiram, MEK/MPK, —LICA97, 1% <1 h 4.0% 95% 4 Disulfiram, MEK/MPK, — 1-Methylimidazole, <1h 4.0% 95% 1% 5 Disulfiram, MEK/MPK, Dicumyl 1-Methylimidazole, <1 h2.5% 95% peroxide, 1% 1.5%

Example 3

Another exemplary series of cure promoter compositions was prepared asshown in Table 3 below. This set of samples in Example 3 illustrate thesynthesis of cure promoter solutions that when applied on uncuredsealant, Royal WS8035, would reduce the time to obtain a tack-freesurface. Each component is expressed in weight percent of the totalweight of the cure promoter composition. Various metal complexes andaccelerators were utilized in the samples within Example 3 and wereprepared similarly to the procedures outlined in the preceding examples.

TABLE 3 Surface Tack Sample Accelerator Accelerator Reducing Free # 1 2Solvent Agent Time 0 Control Sample >3 h   4 Disulfiram, — MEK/1-Methyl- 1 h 4.0% MPK, imidazole, 95% 1% 6 Zinc- MEK/ 1-Methyl- 1 hdisulfiram, MPK, imidazole, 4% 95% 1% 7 Disulfiram, Zinc- MEK/ 1-Methyl-1 h 2% hydrate, MPK, imidazole, 2% 95% 1% 8 Zn- MEK/ 1-Methyl- 1 hdisulfiram MPK, imidazole, 2%, 95% 1% Zn-hydrate 2%

Example 4

Another exemplary series of cure promoter compositions was prepared asshown in Table 4 below. This set of samples in Example 4 illustrate thesynthesis of cure promoter solutions that when applied on uncuredsealant, Royal WS8035, would reduce the time to obtain a tack-freesurface. Each component is expressed in weight percent of the totalweight of the cure promoter composition. Various compatibilizingcarriers were utilized in the samples within Example 4 and were preparedsimilarly to the procedures outlined in the preceding examples with thecompatibilizing carrier added after the accelerator.

TABLE 4 Surface Tack Shore Shore Compatibilizing Free A @ A @Accelerator Reducing Agent Carrier Solvent Time 3 h 4 h ControlSample >3 h Tacky — Disulfiram, 1- Xylenes, 5% MEK/MPK. <1 h 9.57 — 4.0%Methylimidazole, balance 1% Disulfiram, 1- Xylenes, 10% MEK/MPK, <1 h9.47 — 4.0% Methylimidazole, balance 1% Disulfiram, 1- Cyclohexane,MEK/MPK, <1 h 10.67 — 4.0% Methylimidazole, 5% balance 1% Disulfiram, 1-Cyclohexane, MEK/MPK, <1 h 17.13 — 4.0% Methylimidazole, 10% balance 1%Disulfiram, 1- Styrene, 5% MEK/MPK, <1 h 10.60 — 4.0% Methylimidazole,balance 1% Disulfiram, 1- Styrene, 10% MEK/MPK, <1 h 25.63 — 4.0%Methylimidazole, balance 1% Disulfiram, 1- Liquid MEK/MPK,   3 h 18.00 —4.0% Methylimidazole, polysulfide, 5% balance 1% Disulfiram, 1- LiquidMEK/MPK, <1 h 21.9 — 4.0% Methylimidazole, polysulfide, balance 1% 10%Disulfiram, 1- Liquid MEK/MPK, <1 h — 20.7 4.0% Methylimidazole,polysulfide, balance 1% 15% Disulfiram, 1- allyl sulfide, 5% MEK/MPK, <1h 26.37 4.0% Methylimidazole, balance 1% Disulfiram, 1- allyl sulfide,MEK/MPK, <1 h 16.5 23.1 4.0% Methylimidazole, 10% balance 1% Disulfiram,1- allyl sulfide, MEK/MPK, <1 h 10.5 24 4.0% Methylimidazole, 15%balance 1% Disulfiram, 1- Liquid MEK/MPK, <1 h 5.8 23.8 4.0%Methylimidazole, polysulfide balance 1% 10% + Allyl Sulfide 5%Disulfiram, 1- — MEK/MPK, <1 h 17.7 — 4.0% Methylimidazole, balance 1%

Example 5

Another exemplary series of cure promoter compositions was prepared asshown in Table 5 below. This set of samples in Example 5 illustrate thesynthesis of cure promoter solutions that when applied on uncuredsealant, Royal WS8035, would reduce the time to obtain a tack-freesurface. Each component is expressed in weight percent of the totalweight of the cure promoter composition. Various adhesion promoters wereutilized in the samples within Example 5 and were prepared similarly tothe procedures outlined in the preceding examples with the adhesionpromoter added after the compatibilizing carrier.

TABLE 5 Adhesion Adhesion Surface Promoter Promoter Adhesion Tack Comp.Glycidyl Mercapto Promoter Free Accelerator Reducing Agent CarrierSilane Silane LICA 97 Solvent Time Disulfiram, 1- allyl sulfide, 5.00% —— MEK/MPK, <1 h 4.0% Methylimidazole, 15% 75% 1% Disulfiram, 1- allylsulfide, 4.00% 1.00% — MEK/MPK, <1 h 4.0% Methylimidazole, 15% 75% 1%Disulfiram, 1- allyl sulfide, 3.50% 0.75% 0.75% MEK/MPK, <1 h 4.0%Methylimidazole, 15% 75% 1% Disulfiram, 1- 3.50% 0.75% 0.75% MEK/MPK, <1h 4.0% Methylimidazole, 90% 1%

Example 6

Another exemplary series of cure promoter compositions was prepared asshown in Table 6 below. This set of samples in Example 6 illustrate thesynthesis of cure promoter solutions that when applied on uncuredsealant, Royal WS8035, would reduce the time to obtain a tack-freesurface. Each component is expressed in weight percent of the totalweight of the cure promoter composition. Various combinations of thepreceding examples were prepared in the samples within Example 6 andwere prepared similarly to the procedures outlined in the precedingexamples.

TABLE 6 Adhesion Adhesion Surface Promoter Promoter Adhesion Tack SampleComp. Glycidyl Mercapto Promoter Free # Accelerator Reducing AgentCarrier Silane Silane LICA 97 Solvent Time CP1 Disulfiram, 1- 15% — — —MEK/MPK, <1 h 4.0% Methylimidazole, PTMP 80% 1% CP2 Disulfiram, 1- allyl— — — MEK/MPK, <1 h 4.0% Methylimidazole, sulfide, 80% 1% 15% CP3Disulfiram, 1- 15% — — — MEK/MPK, <1 h 4.0% Methylimidazole, PTMP, 75%1% 5% allyl sulfide ACP Disulfiram, 1- 15% 3.50% 0.75% 0.75% MEK/MPK, <1h 4.0% Methylimidazole, PTMP 75% 1%

Example 7

Polysulfide sealant WS8035 was mixed according to the supplierinstructions without any curative and casted on a non-stickfluoropolymer mold. A solution of CP2 from Example 6 was brushed ontothe top surface of the sealant. The sealant was evaluated for a tackfree surface after 1 hour, and was abraded after 4 hours. The sandingwas performed for a minimum duration of 30 seconds using a Makitafinishing sander with a 3M® 7445 Scotch-Brite™ pad. The sample,unabraded, exhibited a glossy tack free surface after 1 hour. Afterabrasion, the sample exhibited a matte abraded surface that was notwrinkled under the pressure of the sander, indicating a complete,accelerated cure.

Application and Testing Methods

After synthesis of the cure promoter compositions the solutions arebrushed or sprayed on uncured sealants as described herein. Testingprotocols are conducted using the following methods as described.Polysulfide sealant samples were prepared as described in the precedingexamples by mixing according to the supplier instructions and castingonto a non-stick fluoropolymer mold.

Tackiness test: polysulfide sealant was casted on a non-stickfluoropolymer mold to a dimension of 1″ by 1″ and a 0.25″ thickness.Immediately follow the casting, the exemplary formulations in theexamples were brushed on top of the uncured sealant. Surface tackinesswas assessed by contacting the sealant surface with a polyester (PET)film. After separating if there is no residue on the PET film thesurface is determined to be tack free.

Shore A test: in some exemplary examples, a Shore A durometer test wasdone by pressing the Shore A durometer on the tack free sealant surfaceand recording the values. Three measurements were done per sample, withthe average of the three values reported.

Power sanding test: in some examples, the tack free surface wassubjected to a sanding by an electric sander (Makita B04556K) with anattached 3M® Scotch-Brite™ 7445 pad as a sanding surface. Samples of 2″by 3″ and a 0.25″ thickness were sanded for at least 30 s. Qualifiedsamples are ones that do not wrinkle and where any dust resulting fromthe sanding can be wiped clean without sticking to the sealant surface.

Liquid deposition: Approximately 0.5 mL of exemplary cure promotercomposition was transferred onto the surface of the uncured sealant bycompletely wetting a clean brush or roller with cure promoter solutionprior to application. Approximately 0.5 mL of promoter solution persquare inch of the uncured sealant is brushed directly onto the sealantsurface. The top of the sealant surface is tack free after 1 hour andcan be sanded after 4 hours. The brushes and rollers can be cleanedafterwards by washing with acetone and isopropanol.

Spray coating: Approximately 10 mL of exemplary cure promotercomposition was transferred to a glass container and the containerhooked to an Iwata airbrush spray gun. The uncured sealant surface wascoated in 1 pass. The top surface of the sealant surface is tack freeafter 1 hour and can be sanded after 4 hours.

The following description of various aspect(s) is merely exemplary innature and is in no way intended to limit the disclosure, itsapplication, or uses.

As used throughout this disclosure, ranges are used as shorthand fordescribing each and every value that is within the range. It should beappreciated and understood that the description in a range format ismerely for convenience and brevity, and should not be construed as aninflexible limitation on the scope of any examples or implementationsdisclosed herein. Accordingly, the disclosed range should be construedto have specifically disclosed all the possible subranges as well asindividual numerical values within that range. As such, any value withinthe range can be selected as the terminus of the range. For example,description of a range such as from 1 to 5 should be considered to havespecifically disclosed subranges such as from 1.5 to 3, from 1 to 4.5,from 2 to 5, from 3.1 to 5, etc., as well as individual numbers withinthat range, for example, 1, 2, 3, 3.2, 4, 5, etc. This appliesregardless of the breadth of the range.

Unless otherwise specified, all percentages and amounts expressed hereinand elsewhere in the specification should be understood to refer topercentages by weight of total solids. The amounts given are based onthe active weight of the material.

Additionally, all numerical values are “about” or “approximately” theindicated value, and take into account experimental error and variationsthat would be expected by a person having ordinary skill in the art. Itshould be appreciated that all numerical values and ranges disclosedherein are approximate values and ranges, whether “about” is used inconjunction therewith. It should also be appreciated that the term“about,” as used herein, in conjunction with a numeral refers to a valuethat can be ±0.01% (inclusive), ±0.1% (inclusive), ±0.5% (inclusive),±1% (inclusive) of that numeral, ±2% (inclusive) of that numeral, ±3%(inclusive) of that numeral, ±5% (inclusive) of that numeral, ±10%(inclusive) of that numeral, or ±15% (inclusive) of that numeral. Itshould further be appreciated that when a numerical range is disclosedherein, any numerical value falling within the range is alsospecifically disclosed.

The present disclosure has been described with reference to exemplaryimplementations. Although a limited number of implementations have beenshown and described, it will be appreciated by those skilled in the artthat changes can be made in these implementations without departing fromthe principles and spirit of the preceding detailed description. It isintended that the present disclosure be construed as including all suchmodifications and alterations insofar as they come within the scope ofthe appended claims or the equivalents thereof.

The present disclosure has been described with reference to exemplaryimplementations. Although a limited number of implementations have beenshown and described, it will be appreciated by those skilled in the artthat changes can be made in these implementations without departing fromthe principles and spirit of the preceding detailed description. It isintended that the present disclosure be construed as including all suchmodifications and alterations insofar as they come within the scope ofthe appended claims or the equivalents thereof.

What is claimed is:
 1. A cure promoter composition, comprising: anaccelerator comprising a thiocarbamate, a hydrated thiocarbamate, adithiocarbamate, a thiazole, a mercaptothiazole, a sulfenamide, athiazolesulfenamide, a metal salt of thiocarbamate, sulfur chloride, orcombinations thereof; a compatibilizing carrier comprisingpentaerythritol tetrakis(3-mercaptopropionate); one or more organicsolvents; and a catalyst, comprising an amidine, a diazole, an amine, apyridine, or combinations thereof.
 2. The cure promoter composition ofclaim 1, wherein the accelerator is disulfiram.
 3. The cure promotercomposition of claim 1, wherein the compatibilizing carrier furthercomprises a monomer, an oligomer, a low molecular weight poly sulfides,a low molecular weight poly thiol, a low molecular weight vinylfunctional compound, an organic solvent, or combinations thereof.
 4. Thecure promoter composition of claim 1, wherein the compatibilizingcarrier further comprises allyl monosulfide, allyl disulfide, ethylvinyl sulfide, phenyl vinyl sulfide, styrene, or combinations thereof.5. The cure promoter composition of claim 3, further comprisingtrimethylolpropane tris(3-mercaptopropionate), 2,2′-thiodiethanethiol,2,2′-(ethylenedioxy)diethanethiol, tris(mercaptoalkyl) cyclohexanes, orcombinations thereof.
 6. The cure promoter composition of claim 1,wherein the one or more organic solvents comprise an aliphatichydrocarbon, an aromatic compound, a ketone, an amine, an ester, analcohol, an aldehyde, an ether, or combinations thereof.
 7. The curepromoter composition of claim 1, further comprising: a reducing agent;optionally, one or more reactive silanes; optionally, one or morereactive organometallics; optionally, one or more gelling agents; andoptionally, an aqueous component.
 8. A cure promoter composition,comprising: disulfiram; pentaerythritol tetrakis(3-mercaptopropionate);one or more organic solvents comprising a ketone; 1-methylimidazole; oneor more reactive silanes; one or more reactive organometallics; one ormore gelling agents; and an aqueous component.
 9. The cure promotercomposition of claim 8, further comprising a monomer, an oligomer, a lowmolecular weight poly sulfides, a low molecular weight poly thiol, a lowmolecular weight vinyl functional compound, an organic solvent, orcombinations thereof.
 10. The cure promoter composition of claim 8,further comprising allyl monosulfide, allyl disulfide, ethyl vinylsulfide, phenyl vinyl sulfide, styrene, or combinations thereof.
 11. Thecure promoter composition of claim 9, further comprisingtrimethylolpropane tris(3-mercaptopropionate), 2,2′-thiodiethanethiol,2,2′-(ethylenedioxy)diethanethiol, tris(mercaptoalkyl) cyclohexanes, orcombinations thereof.
 12. The cure promoter composition of claim 9,wherein the one or more reactive silanes comprises aglycidoxypropyltrimethoxysilane.
 13. The cure promoter composition ofclaim 9, wherein the one or more reactive silanes comprises amercaptopropyltrimethoxysilane.
 14. A method for applying the curepromoter composition of claim 1, the method comprising: contacting theone or more organic solvents, the accelerator, the compatibilizingcarrier, and the catalyst with one another to prepare the cure promotercomposition; homogenizing the cure promoter composition; pausing afterhomogenizing to allow the cure promoter time to react; applying asealant, resin, paint layer, or combinations thereof onto a substrate;and applying the cure promoter composition to a surface of the sealant,resin, paint layer, or combinations thereof.
 15. The method of claim 14,further comprising pausing to allow the sealant, resin, paint layer, orcombinations thereof to cure completely.
 16. The method of claim 14,further comprising abrading the surface of the sealant, resin, paintlayer, or combinations thereof.
 17. The method of claim 14, furthercomprising: contacting a first portion comprising the one or moreorganic solvents, the accelerator, and the catalyst in a firstcontainer; contacting a second portion comprising the one or moreorganic solvents, the compatibilizing carrier, and the one or morereducing agents in a second container; and contacting contents of thefirst container with contents of the second container prior to applyingthe cure promoter composition to the substrate.
 18. The method of claim14, wherein the substrate comprises an aluminum surface, a carbon fibercomposite surface, or combinations thereof.
 19. A method for applying acure promoter composition, comprising: contacting one or more organicsolvents, an accelerator comprising a thiocarbamate, a hydratedthiocarbamate, a dithiocarbamate, a thiazole, a mercaptothiazole, asulfenamide, a thiazolesulfenamide, a metal salt of thiocarbamate,sulfur chloride, or combinations thereof, a compatibilizing carrier, oneor more optional reactive silanes, one or more optional organometallics,and a catalyst with one another to prepare a cure promoter composition;homogenizing the cure promoter composition; applying a sealant, resin,paint layer, or combinations thereof onto a substrate; applying the curepromoter composition to a surface of the sealant, resin, paint layer, orcombinations thereof; evaporating the one or more organic solvents fromthe cure promoter composition; and pausing to allow the cure promotertime to react.
 20. The method of claim 19, wherein the contacting one ormore organic solvents, an accelerator comprising a thiocarbamate, ahydrated thiocarbamate, a dithiocarbamate, a thiazole, amercaptothiazole, a sulfenamide, a thiazolesulfenamide, a metal salt ofthiocarbamate, sulfur chloride, or combinations thereof, acompatibilizing carrier, one or more optional reactive silanes, one ormore optional organometallics, and a catalyst with one another toprepare a cure promoter composition further comprises contacting one ormore gelling agents.